Gas burner with selective flame distribution



J. H. FLYNN 2,869,630

GAs BURNER WITH sELEcTIvE FLAME DISTRIBUTION Jan. 20, 1959 4 SheetsSheet 1 Filed April 28. 1954 INVENToR. T Job/7 HFZJ/Ym J. H. FLYNN Jan. 20, 1959 GAS BURNER WITH SELEICTIVE FLAME DISTRIBUTION l Filed April 28. 1954 4 Sheets-Sheet 2 @TQM ` JNVENTOR.

50272719' F'Q/m y Jan. 20, 1959 J. H. FLYNN 2,869,530

GAS BURNER WITH SELECTIVE FLAME DISTRIBUTION Filed April 28. 1954 4 sheets-sheet s NVENTORA JCP/2275 F5072? @d0/WW.

J. H. FLYNN Jan. 2o, 1959 GAS BURNER WITH SELECTIVE FLAME DISTRIBUTION Filed April 28; 1954 4 Sheets-Sheet 4 lINVENTOR. Jaw? HAZ/)0727 United States Patent O GAS BURNER WITH snLEcTIvE FLAME DISTRIBUTION John H. Flynn, New Rochelle, N. Y.

Application April 28, 1954, Serial No. 426,141

7 Claims. (Cl. 158-105) This invention relates to gas burners in general, and to gas burners with selective ame distribution in particular.

Band oven and similar burner operations frequently require selective llame distribution over the available iiame space of any or all burners used for that purpose. This has heretofore been achieved in either one of two different ways.

Thus, in one previous burner construction of selective llame distribution several separate burner sections are arranged end-toend to form a burner aggregate for the production of a more or less continuous flame across the width of an associated traveling conveyor band, for instance, and each burner section of this aggregate is supplied with gas from a separate conduit and under the control of a separate valve, thereby to regulate the llame from each burner section and obtain any required flame distribution, While this section-type burner performs satisfactorily insofar as flame distribution is concerned, it leaves much to be desired in other respects. Thus, the requirement of separate gas conduits for the separate burner sections of the burner aggregate not only complicates the burner installation but adds prohibitively to the overall cost of the latter, especially if the installation should require a large number of these burner aggregates side-by-side over an extended heating zone. Moreover, the additional requirement of individual valve control for each separate burner section of each burner aggregate complicates the burner installation even further and increases its overall cost still more.

In a previous alternative form of burner construction for this purpose, gas in variable amounts is introduced, from one end of a burner, selectively either directly into this one burner end or, through an internal tube, into the other burner end, or both, in an endeavor to obtain llame distribution to meet the varying demands of a` particular burner operation. However, this alternative inner-tube type burner affords a measure of ilame distribution which is inadequate for many purposes. Thus, the best that can be achieved in the Way of flame distribution, outside of a flame of substantially uniform height throughout the available llame space, is a gradual tapering oit of the flame, and the region within which the flame may taper olf cannot be effectively varied without increasing or decreasing the gas flow and, hence, Varying the maximum height of the ilame. Moreover, this burner must have considerable minimum llame space, and for a rated maximum heat output cannot exceed a certain maximum ame space, in order to aiford even the aforementioned limited llame distribution.

It is the primary object of the present invention to provide a gas burner of the selective ame distribution type which has none of the aforementioned shortcomings of the previous burners and in construction and performance is superior to the latter.

Thus, it is among the objects of the present invention to provide a burner of this type having successive zones in the over-allflame space of the burner over which selective tlame distribution is desired, and a'single internal control unit for all zones operable from the outside of the burner in order selectively to admit gas from a single fice external conduit to selected zones, and thereby achieve any desired distribution of the ame over the available llame space of the burner.

It is another object of the present invention to provide a burner of this type of which the aforementioned control unit is a valve mechanism extending through partitioned channel sections into which the burner interior is divided and having a multi-ported valve conduit which is solely relied on to supply gas to the channel sections.

The valve mechanism is movable Within said conduit intoA any one of a number of predetermined positions in which: to provide communication between said conduit, through diiferent combinations of valve ports, with any one of these channel sections or certain combinations thereof.

. In addition, it is an object to provide a valve arrangement which will permit removal of the control unit endwise of the burner, externally of the oven or other heating unit in which the burner is located, for proper cleaning, servicing or replacement if necessary, without disturbing the rest of the installation.

, It is a further object of the present invention to provide a burner of this type in which the aforementioned valve mechanism has provisions for admitting into any channel section or sections, which happen tot be shut off from the gas supply by the aforesaid multi-ported valve conduit in any of its predetermined positions, suicient gas to sustain in the corresponding zone or zones of the llame space of the burner a pilot-type flame or ames, thereby merely to suppress, rather than fully extinguish, the ilame in any zone which is shut off by the valve conduit, and permit instantaneous variation of the ilame distribution while the burner is operating without involving any of the hazards springing from the `escape of nonignited gas. v

A further specific object is to provide a simple burner control which will indicate externally of the oven the type of ame pattern or distribution provided by any setting of the control.

Another object of the present invention is to provide a burner of this type in which the aforementioned valve mechanism comprises a xed conduit which receives gas from an external supply line and extends through, and has outlet ports to, the successive channelsections of the burner, and a multi-ported operating member which is movable from the outside of the burner into predetermined positions in which one or more of its ports are in registry with one or more of the outlet ports in the fixed conduit for any desired flame distribution over the designated zones of the available ilame space of the burner.

A further object of the present invention is to provide a burner of this type in which the aforementioned xed conduit of the internal valve mechanism is further provided, n addition to its regular outlet ports, with restricted pilot ports which are permanently open to the several channel sections of the burner and admit to the same suiiicient gas for sustaining the aforementioned pilot llame or flames in whichever zone or Zones of the overall ame space of the burner the flame is to be suppressed in accordance with the particular setting of the aforesaid operating member of the valve mechanism.

It is ano-ther object of the present invention to provide a burner of this type in which the aforementioned operating member of the internal valve mechanism may be a tubular valve which is turnable on, and preferably in,

the aforementioned fixed conduit of the valve mechanism, and has within the confines of each channel section' of the burner a series of angularly spaced ports for the registry of either with the corresponding outlet port in the fixed conduit in certain ones of a number of prel determined angular positions of the tubular valve.

assenso It'is a" further object of the' present invention to provide a bur-ner of thistypev inwhichY the aforementioned operating member of the internal valve mechanism may, alternatively, be a reciprocablevalve which is longitudinali-y14 slide-ble' on,and preferably in; the aforementioned fik'ediconduit of the valve mechanism, and'has within the` contines of each channel sectionof' the burner a series of longitudinally spaced ports for' the registry of either with the' corresponding outlet port in the xed con-duit in certainones ofA a' number ofV predetermined longitudinal positiensof the reciprocable valve.

Ariothe'r'ob'ject of thefpresent invention is tov provide ab'urner of? this type with an alternative pilot arrangernent; by continuing the aforementioned pilot ports in the fixed conduit of they internal valve' mechanism, tirst through the" partitions irithe burner channel andfthence through pilot tubes, into close proximity to the burner port between the aforementioned zones of the flame space ofthe burner there to sustain isolated pilot dames for servicing these dame* zones.

Eurther objects and advantages will appear to' those skilledj in theart fromv thev following, considered in conjunctionwith'the accompanying drawings.

In the accompanying drawings, in which certain modes oiicarryingtou'tthe present invention are shown for iliustrat-ive'v purposes: Fig; l is a longitudinal section through a burner em'- bodyi'ng'A the present invention;

Figs. 2, 3 and 4 are enlarged'cross-sectons through theburn'er astaken on the lnesE-Z, 3 3 and EQ-4', respectively, of Fig; l;

yFig. 5 is anI` enlarged fragmentary View of a part of the burner as viewed inl the direction of' the arrow in Fig-3iv` Fig; 6-is` avieu/'of the burner, partl'y'in longitudinal section-'and' partly in' elevation;

Fig-7 is arren'l'argedv crosslseotio'n through the burner as taken on the line 7 7 of Fig. 6;

Figs; 8to14, inclusive, aref diagrammatic views of they burner', illustrating dilier'ent dame distribution {patterns obtai'nable by virtue of the valve mechanism in the burner; p

Figs.- SmYSZi, to 14d, l/ib, 14e are diagrammatic cross-sections throughthe Valve mechanism inthe burner inl'diferent operating positions in which to obtain the iia'me distribution'patterns of Figs.` 8 to 14, respectively;

Fig; 15 `is affragmentary longitudinal section through af-burner enibody'iing the present invention inta modiiied illvlne'r;-L

Fig.V 16 is aV fragmentary longitudinal section throughl a'burner embodying the present inventionv in another' modiii'edmann'er; y Fig.V 17 is a fragmentary longitudinal sectionthro'u'gh a burner embodying the present invention in a further modiiied manner; Y

Fig. 18 is a section taken on the line 1d-i8 of Fig. 17; Fig.: 19 is a fragmentary longitudinal'section through atrburner embodying the present invention in still another' modified manner; and

Figs. 20, 2l and 22 are sections taken on the lines 21)#26, M-Zi and 22-22, respectively, of Fig. 19.

Referring to the drawings, and'more' particularly to Figs. l to 7 thereof, the reference numeral 3d kdesignates ae gas burner having a burner casing 32 which is provided Awith a longitudinali channel 34 for conducting gas to the burner ports. The instant burner 3d is, by Way ofl example, shown to be of the ribbon-type disclosed inV my prior Patent No. 2,647,569, dated August 4, 1953. To this end, the burner casing 32'; is provided with a high-pressure burner port or slot 36 and anking lowpressure ports or grooves 35 in which are mounted sets ofiburner ribbons Lid', 42 and' d4, respectively. The burnerslot 36- is in direct communication'with the'channel-34fas at 37,-whiie the burner grooves 3S communicate with the-fburnerf-slot throughfrestricted 'ducts 39 pro- V 75 vided at spaced intervals therealong (Figs. l, 2, and 4). The burner ribbons of each set may be alike and consist of major ribbons 46 and minor ribbons 43 (Fig. 5) which are so arranged as to provide high, medium and low velocity gas passages 5t?, 2 and 54, respectively. Hence, the tiame at each of thel burner ports 36, 38 is formed of high, medium andllow ame components of which the low an'i'e components support the medium flame components and the latter support the high flame components. The iiarne at the .burnerl port or slot 36, being fed by gas of greater velocity and volume than the flames at the burner ports 38, i's considerably higher than the latter iiames and is further sustained thereby.

Pursuant to the objective of the' present invention to obtain selective iiame distribution over the flame space of the burner, thechannel 34 in the burner casing 32 is divided by"Y transverse partitions 56 thereinv into'as many channel sections 5 8 as the desired number ofiianie' zones 6i) of thewover-all flame space'sover which the iiarnes maybe distributedfin Various patterns. In the present example, two partitions 56 divide the channel 34 into three sections 58. Further, there is provided valve mechanism 62 for controlling the flow of gas into the several channel sections 58'. l u

The valve mechanism 62 comprises a casing 64 and an operating valve 66. The valve casing 64 is, in the present instance, in the` form of a cylindrical conduit which entendsthroughoutV the channel 34 and is suitably mounted in the' partitions 56 thereinV and in sleeves 68 and on the end" walls 72 and 74, respectively, ofthe burner casing 32. The'conduit 64 is provided within `the successive channel sections 55h, 58h and 58e with outlet ports 76a, 76H and 761e,` respectively, which are prefer.-1 ably at Vthe bottom of the conduit 64 so as to permity maxidistribution fof .the gas issuing therefrom Vin the respective `'channel sectionsl SSf'for a most unitormy gas ow through" the burnerportswithin the vrespective ame zones o0. The sleeveiil is connected with la gas supply pipe 78 through a T iitting the open'end 32 of Whichfisl closed by'a preferably removable Vcover 84 (Fig. l). The sleeve 70y on theiother end ofA the burner casing`32 is closed by` a cover Sfmwhich is bolted at S8 to a head 90 onthe sleeve 470,4 and'hasan annular rib 921m retaina packing 94'in the head 90 in sealing engagement with the vc onduit 64 L v The operating'yva'lve 66l comprises,`in theV present" in,-` stance,a'pluralityof'sleeve-type valves 96, one foreach channel section 58.` The ends of the sleeve valves 96 are connected by s'pidfers98 with hubs wtiwhich are mounted'on a common opeerating rod 102.H The rod 102 isjournalled in'y the' covers 84 and 86 and'extends 1beyond the'covler 84- i'ntoavhousing ltii'th'ereon the open frontend tti'of which yis normally closed by a Vpiv'oted cover 108 (Fig."n1)v. Preferably, a packing 31.1.0y isl provided in theY cover Si'to'prevent gas from leaking along the operating" rod` 1.02. yThe 'end'of 'the operating rod iiilwhich eX-z providediwithfa pointer 113 to cooperate withY a dial or' marksy .(neither` shownion the adjacent face ofthe cover.v 3f: toindic'ate `the aforementioned predetermined angular' positions of theopera'ting rodand sleeve valves thereon'.l Eachusleeve valve 96 is provided with a series of circumferential ports lltlsome of which are" contiguous` with eachothenandothers are spacedrfrom eachY other.

Thus the sleeve valve 95a in the channel section 58d (Figs. 1 and 2) has, in this example, ports 13.451 of which three areicontiguous and one is spaced from them by'a wall portion 116 of thesleeve` valvewhich inwid-this-substantiallyequal to that of a single port. The sleeve valve 96kmtheChannetsecfgnzb (Eastland 3) has perfs 11412 'whio ,.1 in this example, are arrangedlikethe ponts 114a(-F1g-.2.)f but are angularly displacedffrom the latter by one port width. The sleeve valve 96e in the channel section 58e (Figs. l and 4) has, in this example, four contiguous ports 114e.

With the exemplary port arrangement in the sleeve valves 96 as described and illustrated in Figs. 2 to 4, the instant burner 30 may he operated in accordance with any of the llame distribution patterns shown in Figs. 8 to 14, inclusive. Thus, in the angular positions ot the sleeve valves 96a, 96h and 96C in Figs. Sa to 8c, the llame distribution pattern of Fig. 8 will be achieved. This follows from Figs. 8a to 8c which show that a port 114:1 in the sleeve valve 96a registers with the outlet port 76a in the conduit 64, while no ports in the other sleeve valves 96b and 96C register with the outlet ports 76h and 76e, respectively, in the conduit 64, with the result that only the channel section 56a receives gas for sustaining a utility llame f over the flame zone tla (Figs. 1 and 8).

On turning the sleeve valves 96 into the angular positions shown in Figs. 9a to 9c, ports 114e and 114b in the sleeve valves 96a and 96b register with the outlet ports 76a and 76h, respectively, in the conduit 64 (Figs. 9a and 9b), while no port in the sleeve valve 96C registers with the outlet port 76C in the conduit 64 (Fig. 9c). Accordingly, the channel sections 58a and 58h receive gas and the channel section 58C receives no gas, with the result that a continuous utility ame extends over the adjoining llame zones 60a and 60b (Figs. 1 and 9). On turning the sleeve valves 96 into the angular positions shown in Figs. 10a to 10c, ports of all sleeve valves register with the respective outlet ports in the conduit 64. Accordingly, all channel sections 5S receive gas for sustaining'a continuous utility flame f which extends over the llame zones 60a, 66h and 60e, i. e. over the entire flame space of the burner (Fig. 10).

lOn turning the valves 96 into the angular positions 1 shown in Figs. 11a to llc, ports 114b and 114C in the sleeve valves 96h and 96C register with the outlet ports 76h and 76C, respectively, in the conduit 64 (Figs. 1lb and llc), while no port in the sleeve valve 96a registers with the outlet port 76a in the conduit 64 (Fig. 11a). Accordingly, the channel sections SSb and 58e receive gas and the channel section 58a receives no gas, with the result that a utility flame f is sustained which extends over the adjoining flame zones 60h and 60C (Fig. l1).

i On turning the sleeve valves 96 into the angular positions shown in Figs. 12a to 12C, a` port 114C in sleeve valve 96e registers with the outlet port '76C in the conduit 64 (Fig. 12C), while no ports in the sleeve valves 96a and 96h register with the outlet ports 76a y and 76h, respectively, in the conduit 64 (Figs. 12a and 12b). Accordingly, the channel section 58C is the only one which receives gas, with the result that a utility llame f is sustained which extends over the flame zone 60e (Fig. 12).

On turning the sleeve valves 96 into the angular positions shown in Figs. 13a to 13C, ports 114e and 114C in the sleeve valves 96a and 96C register with the outlet ports 76a and 76C, respectively, in the conduit 64 (Figs. 13a and 13e), while no port in the sleeve valve 96]: registers with the outlet port 76h inthe conduit 64 (Fig. 13b). Accordingly, the channel sections 58a and 58e receive gas and the channel section h receives no gas, with the result that spaced utility flames f are sustained which extend over the llame zones Gila and C, respectively (Fig. 13).

Finally, on turning the sleeve valves 96 into the angular positions shown in Figs. 14a to 14C, a port 114]; in the sleeve valve 96h registers with the outlet port 7617 in the conduit 64 (Fig. 1417), while no ports of the sleeve valves 96a and 96C register with the outlet ports '76a and '76e in the conduit 64 (Figs. 14a and 14C). Accordingly, only the channel section SSb receives gas, with the result that a utility flame f is sustained which extends over the llame zone 60h (Fig. 14).

The exemplary llame distribution patterns described 6 hereinbefore and shown in Figs. 8 to 14, inclusive, may of course be varied to meet most any requirements, simply by coordinating the ports in the several sleeve valves 96 in a manner which is clearly indicated by the series of Figures 8a to 8c, 9a to 9c, etc. These same series of ligures give also a clear indication of the manner in which the ports in a different number of sleeve valves may be coordinated if the over-all ame space of the burner is to be divided into a different number of zones over which the llames may selectively be distributed.

Suitable provisions are also made to sustain a pilot flame f' (Figs. 8 to 14) in any llame zone 60a, 60b or 60e which during operation of the burner is shut olrfrom the gas supply in the conduit 64 by the corresponding sleeve valve 96 therein, thereby to permit instantaneous variation of the llame distribution pattern of the burner without risking any of the dangers springing from the escape of non-ignited gas. To this end, the conduit 64 is within the contines of the channel sections 58 provided with restricted pilot ports 120 (Figs. 6 and 7) which provide permanent communication between the interior of the conduit 64 and these channel sections for the escape into the latter of suliicient gas to sustain in any shut-oli llame zone or zones 60 a suppressed pilot-type llame or flames f.

Fig. l5 shows a modiiied gas burner 130 which distinguishes from the hereinbefore described burner 30 by having provisions for sustaining restricted pilot flames f" between and in igniting relation with adjacent llame zones 60 of the burner, rather than sustaining a depressed pilot ilame sheet or sheets throughout the flame Zone or zones which in any particular setting of the valve mechanism may be shut oit by the latter. To this end, pilot ports 132 in the conduit 64 of the valve mechanism register with ports 134 in the several partitions 56', respectively, in the channel 34 in the burner casing 32', and pilot tubes 136 may be used to extend the pilot ports into even closer proximity to the burner ribbons in the burner slot 36 to sustain the isolated pilot flames f" at their designated locations.

Fig. 16 shows another modified gas burner 140 which may in all respects be like the hereinbefore described gas burner 30 in Figs. 1 to 7, except that the operating valve 66 is in the form of a continuous tube which is rotatable in the conduit 64". The tube 66" has, within the conlines of the several channel sections 58, the same or similar port arrangements 1.14" as the sleeve valves 96 in the burner 3).

Fig. 17 shows another modified gas burner 150 which distinguishes from the previously described forms of the burner by having a sliding valve 66 in the conduit 64 in the burner casing. For the sake of simplicity, the channel 152 in the burner casing is divided by a transverse partition 154 into only two channel sections 156 and 158. Accordingly, lthe conduit 64 has only two outlet ports 160 and 162 which communicate with the channel sections 156 and 15S, respectively. The sliding valve 66"' comprises in this instance two valve plates 164 and 166 which through webs 168 and 170 are connected with an operating rod 172 that is guided for axial motion and may be manipulated back and forth from the outside of the burner in any suitable manner. Each of the valve plates 164 and 166 is provided with a series of ports 174, in this instance two, which in the case of the valve plate 164 are separated from each other and in the case of the other valve plate 166 are lengthwise contiguous with each other. In the axial position of the valve 66 shown in Fig. 17, ports 174 of both valve plates 164 and 166 register with the respective outlet ports and 162 inthe conduit 64'", with the result that both channel sections 156 and 158 receive gas to sustain a utility flame which extends continuously over the entire ilame space of the burner. On axially shifting the valve 66" to the right from the position shown in Fig. 17 through a distance substantially equal to the length of any of the ports 174, the inner one ofthe contiguous ports 174 in the valve plate 166 will @gister with the adjacent outlet; port ,1,62 `in the `conduit 64 and a web.po rtion176 of the rothervalve plate 164 ,n eri the ports 174 thereinwill then close the adjacent outlet port,k i160," with the result that gaswill beadmitted onlyinto the channel section '8to sustain a utility llame which extends over thel corresponding vzone 178k of the over-all flamespace of the burnen On shifting the valve 66" stillufurther. to the right (Fig. 17) into a, position in which aweb portion .180 of the valve .plate 166 will close the adjacent outlet portaldZ in the` conduit 64"', the port 174 in theother valvewplate 1,64 will register with the adjacent outlet port, 160 in theconduit 64" and thus admitgas intothel adjacent lchzlnnel-section 15o to sustain Iautility flame in the corresponding zone 182 of the over-all tlame space oftthe burner. Y i

V.,Figs. 19 to 22, inclusive, show a further modiiied burner 150 the valve mechanism of which comprises a single tube 192 that is turnable ina cylindrical passage 194 in the burnericasing 19.6, having Iin this exampleV a single burner port or slot 193 without any burner ribbons. The tube 192," `which is in communication` With a gas' supply, is provided `within successive lengths v,wi'thseries of portsZlltl, ZMan'd 264, respectively. Depending on the angular positions of the tube 1&2 in the `passage 194, `one or more ofthe series portswill register with the corresponding length or lengths of thenburner port 198Hto admit gas thereinto for sustaining va utility `flame or llames,thereat In the angular position of the tube 192 shown in Figs. l9rto 22, one of they ports'ziitly registers with a corresponding length ofl the burner port 198 (Fig. 20), while all ther other ports 202 and 204 are `out `of registry with ythe burner port (.Figs. 2`1fvand 22'), withthe result that a utility llainewill be sustained over a zone 206 similar to the llame distribution patter'nof Fig. 8. The exemplaiy coordination ofthe ports e, 2oz and 21M in the tube 192 is such that the flame distribution patterns of Figs. 9 to 14, inclusive, will beachieved on successive turns, respectively, of the tubefclockvvise from the positionshown inuFigs. 20A to 22 in steps substantially equal to the width of any single port. l

Any suitable provisions may be made to sustain a pilot llame in any of the llame zones-of the burner which in any particular setting of the tube 192 may be shut ofi. In the present example, there lare providedwin the cylindrical Wall of the passage 19,4 grooves 2118 of restricted cross-sectional area .which Within the respective lengths of the port series 200, 2112 and 204 may extend as shown in Figs. 20 to 22, so as to permit the passage of piloting gas to the burner port 193 in any of the predetermined angular positions of the tube.y

The invention may be carried out in other specific Ways than those herein settorth without departing from the spirit` andressential characteristics ofthe invention, 'and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the` meaning" and equivalency range of the appended claims are intended to be embraced therein.

Nhat is claimed is: Y 4

1. A gas burner having provision for selective ame distribution along its extent, `comprising an elongate, generallyV tubular burner casing having side and end walls defining a longitudinalchannel, a slot` comprising a burner port formed in one side wall and extending substantially the full length thereof in communication With said channel, transverse partitions in said channel dividingv tlie same into sections, said partitions and end walls being provided with `axially aligned apertures, separable closure means at each end of said burner casing, said meansbeing tubular and being secured in the respective end wall apertures in said casing to formv a gastight lit therewith, a separable .tubular gas `conduit extending completely through said longitudinal channeland into tli'e tubiilar. closure meansat each Vendof said casing,

sa'idu conduit being received in close fitting telescoping relation within said closure means at each of its ends and forming a close sliding fit with said aligned partition. apertures intermediate its ends, one of said end closure means having provision for supplying fuel gas to` said conduit, saidY conduit having an outlet port formedin each `of said channel sections, and valve meanscornv prising a single control member extending through said conduit into supporting', engagement with each of said end closure means, said control-member having porte closing means disposed within said conduit ladjacent each of said conduit outlet ports, respectively, which are movable simultaneously by said member into selected posit tions in which different single and combined conduit ports are opened and closedto said channel sectionskto provide selective lamel distribution, said control member projecting through oneof said closure membersand provided with sealing means thereat vto prevent escape of gas but permitting' manual adjustment of said control member externally of said burner casing.

2. A gas burner as defined in claim l, in which said gasl conduit is further provided Within each of-l said channel sectionsl with a permanently open restricted [gas outlet for sustaining ka pilot flame at the several-.burner port lengths corresponding with the sections into which said longitudinal channel is divided. v

3. A gas burner as defined in claim l, in Whicheach partition is provided with an internal passage opening at its outer end into said burnerY casing port and at` its inner end `on the periphery of said aperture, and `said conduit is provided with continuously open ducts aligned, respectively, with said, internal passages to kdirect: gas from the interior of said conduit to said burner port for sustaining a pilot flame thereat. ,t

4. A gas burnervas dened in claim ,1,y wherein said control member comprises a rod extending coaxially of said conduit and said port closing valve means comprise open-ended tubular sleeves each making a bearing fit within said conduit at the respective ported areas thereof, said sleeves being provided with apertures Whichcoincide with the respective conduit ports` in diierentrotated positions of said sleeves and being secured to said control rod for rotative adjustment in unison thereby. l

5. A gas burner as dened in claim 4, wherein the,

ports in said sleeves are of different circumferential extent and of different angular positions about the axis of said sleeves.

6. A gas burner as defined in` claim l, wherein `said control member of said conduit and slidable axially thereof, saidport closing valve means comprising valve plates each, secured.

to said rod adjacent a port of said conduit, said plates being apertured for different axial extents and at diierentg relative positions axially of said conduit to open and close said conduit ports upon longitudinal adjustment of said rod to provide said selective llame distribution.

-7. A gas burner as defined in claimi, wherein said,

control member comprises a tube rotatively., received within said conduit, said tube having apertures in each.2 of said sections, said apertures cooperatingwithpthe respective ports in said conduit and being of diierent circumferential extent and angular position aboutthe' axis of said tube to provide said selective llame distribution upon rotative adjustment of said tube.

1eferences Cited in the leofy this patent UNITED STATES PATENTS comprises a rod extending longitudinally 

